We are studying the relations between the brain hormone (PTTH), the central nervous system and the behaviour of wondering prior to pupation of Manduca sexta. We are isolating the brain hormone, studying the influence of serotonin and glutamic acid on cyclic AMP and cyclic GMP accumultion, and relating these changes to the wandering that occurs prior to pupation. BIBLIOGRAPHIC REFERENCES: Taylor, Duncan P., Dyer, K.A. and Newburgh, R.W. "Cyclic Nucleotides in Neuronal and Glial Enriched Fractions from the Nerve Cord of Manduca sexta" J. Ins. Physiol. 22, 1303 (1976). Taylor, Duncan P., and Newburgh, R.W. "Neural Transmission and Cyclic Nucleotide Accumulation in a Lepidopteran Central Nervous System" Nature (1977).